Liquid crystal display device

ABSTRACT

There is provided an MVA type liquid crystal display device having high brightness and excellent display quality. The liquid crystal display device includes a pair of substrates disposed to be opposite to each other, a liquid crystal sealed between the pair of substrates, plural pixel areas each including a pixel electrode  16   a  formed on one of the substrates and a pixel electrode  16   b  separated from the pixel electrode  16   a , a TFT  20  disposed in each of the pixel areas and including a source electrode  22  electrically connected to the pixel electrode  16   a , a linear projection  42  formed on the other substrate and to regulate alignment of the liquid crystal, and a control capacitance section to capacity couple the source electrode  22  and the pixel electrode  16   b  and including a control capacitance electrode  33  which is electrically connected to the source electrode  22 , is opposite to at least part of the pixel electrode  16   b  through an insulating film, and at least part of which is disposed to overlap with the linear projection  42  when viewed perpendicularly to a substrate surface and extends along the linear projection  42.

This application is a continuation of U.S. patent application Ser. No.11/333,548 filed Jan. 18, 2006, now U.S. Pat. No. 7,471,348 which claimspriority under 35 U.S.C. §119(a) on Japanese Application 2005-011519filed Jan. 17, 2005, all of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an MVA (Multi-domain VerticalAlignment) type liquid crystal display device in which one pixelincludes plural alignment areas different from each other in thealignment direction of liquid crystal molecules, and particularly to aliquid crystal display device in which a pixel area is divided intoplural sub-pixels.

2. Description of the Related Art

A liquid crystal display device is thin and lightweight as compared witha CRT (Cathode Ray Tube), and has merits that it can be driven by lowvoltage and its electric power consumption is small. Thus, the liquidcrystal display device is used for various electronic devices such as anotebook PC (personal computer), a PDA (Personal Digital Assistant) anda cellular phone. Especially, an active matrix type liquid crystaldisplay device in which a TFT (Thin Film Transistor) is provided as aswitching element for each pixel has high drive capability. Since theactive matrix type liquid crystal display device has excellent displaycharacteristics comparable to a CRT, it comes to be used for a use forwhich a CRT is conventionally used, such as a desktop PC or a televisionreceiver.

FIG. 15 shows a rough sectional structure of a conventional liquidcrystal display device. As shown in FIG. 15, the liquid crystal displaydevice includes a liquid crystal display panel 101. The liquid crystaldisplay panel 101 includes a TFT substrate 102 on which a TFT and apixel electrode are formed for each pixel, an opposite substrate 104 onwhich a color filter (CF) and a common electrode are formed, and aliquid crystal 106 sealed between both the substrates 102 and 104. Sincea connection terminal is provided, the TFT substrate 102 is formed to belarger than the opposite substrate 104. Both the substrates 102 and 104are bonded to each other through a sealing material 152 applied to anouter peripheral part. A cell gap between both the substrates 102 and104 is kept by, for example, spherical spacers 146. Besides, polarizingplates 187 and 186 are disposed at both the outsides of the liquidcrystal display panel 101. A backlight unit (not shown) is disposedbelow the polarizing plate 187 in the drawing.

Conventionally, a TN (Twisted Nematic) mode liquid crystal displaydevice is widely used which includes a horizontally aligned liquidcrystal having positive dielectric anisotropy and in which a liquidcrystal molecule is twist-aligned. However, the TN mode liquid crystaldisplay device has defects that a viewing angle characteristic is poorand when a screen is viewed from an oblique direction, the contrast andhue are remarkably changed. Thus, a VA (Vertically Aligned) mode liquidcrystal display device having an excellent viewing angle characteristicand an MVA type liquid crystal display device have been developed andhave been put to practical use.

FIGS. 16A and 16B schematically show sectional structures of an MVA typeliquid crystal display device. A vertically aligned liquid crystal 106having negative dielectric anisotropy is sealed between a TFT substrate102 and an opposite substrate 104. A bank-shaped linear projection 143as an alignment regulating structure to regulate the alignment of theliquid crystal 106 is formed on a pixel electrode 116 of the TFTsubstrate 102. A vertically aligned film 150 made of, for example,polyimide is formed on the pixel electrode 116 and the linear projection143.

A bank-shaped linear projections 142 as an alignment regulatingstructures is formed on a common electrode 141 of the opposite substrate104. The linear projection 142 is extended in parallel to the linearprojection 143 on the TFT substrate 102 side, and is arranged to beshifted from the linear projection 143 by a half pitch. A verticallyaligned film 151 made of, for example, polyimide is formed on the commonelectrode 141 and the linear projection 142.

In the MVA type liquid crystal display device, in a state where avoltage is not applied between the pixel electrode 116 and the commonelectrode 141, as shown in FIG. 16A, almost all liquid crystal molecules108 are aligned almost perpendicularly to the substrate surface.However, the liquid crystal molecules 108 in the vicinities of thelinear projections 142 and 143 are aligned almost perpendicularly to theinclined surfaces of the linear projections 142 and 143.

When a specified voltage is applied between the pixel electrode 116 andthe common electrode 141, the liquid crystal molecules 108 are inclinedwith respect to the substrate surface by the influence of an electricfield. In this case, as shown in FIG. 16B, the inclined directions ofthe liquid crystal molecule 108 are different at both sides of each ofthe linear projections 142 and 143. By this, the so-called alignmentdivision (multi-domain) is realized.

As shown in FIG. 16B, in the MVA type liquid crystal display device,since the inclined directions of the liquid crystal molecules 108 at thetime when the voltage is applied are different at both sides of each ofthe linear projections 142 and 143, the leakage of light in an obliquedirection is suppressed, and an excellent viewing angle characteristicis obtained.

In the above example, although the description has been given to thecase where the alignment regulating structures are the linearprojections 142 and 143, a slit obtained by partially removing anelectrode or a recess (groove) of a substrate surface may be used as analignment regulating structure. Besides, in FIGS. 16A and 16B, althoughthe description has been given to the example in which the alignmentregulating structures are provided on both the TFT substrate 102 and theopposite substrate 104, the alignment regulating structure may be formedonly on one of the TFT substrate 102 and the opposite substrate 104.

FIG. 17 shows an example in which a slit 145 as an alignment regulatingstructure is formed only in a pixel electrode 116 on a TFT substrate 102side. The electric field is distorted in the vicinity of the slit 145,and the electric line of force extends in an oblique direction withrespect to the substrate surface, and therefore, the inclined directionsof liquid crystal molecules 108 are different at both sides of the slit145. By this, the alignment division can be realized and the viewingangle characteristic is improved.

FIG. 18 shows a structure of one pixel of an MVA type liquid crystaldisplay device in which a slit 145 is formed on a TFT substrate 102side, and a linear projection 142 is formed on an opposite substrate 104side. FIG. 19 shows a sectional structure of the TFT substrate 102 cutalong line X-X of FIG. 18. As shown in FIG. 18 and FIG. 19, plural gatebus lines 112 extending in the horizontal direction in the drawing andplural drain bus lines 114 extending in the vertical direction in thedrawing are respectively disposed at specified pitches on the TFTsubstrate 102. Rectangular pixel areas are defined by the gate bus liens112 and the drain bus lines 114. Besides, on the TFT substrate 102, astorage capacitor bus line 118 is formed to be arranged in parallel withthe gate bus line 112 and to cross the center part of each of the pixelareas. An insulating film 130 is formed between the drain bus line 114and the gate bus line 112 or the storage capacitor bus line 118. Thegate bus line 112 and the drain bus line 114, and the storage capacitorbus line 118 and the drain bus line 114 are electrically isolated by theinsulating film 130.

A TFT 120, a pixel electrode 116 and a storage capacitor electrode 119are formed for each of the pixel areas. The TFT 120 uses a part of thegate bus line 112 as its gate electrode. Besides, a drain electrode 121of the TFT 120 is connected to the drain bus line 114, and a sourceelectrode 122 is formed at a position opposite to the drain electrode121 across the gate bus line 112. Further, the storage capacitorelectrode 119 is formed at a position opposite to the storage capacitorbus line 118 across the insulating film 130.

The storage capacitor electrode 119, the TFT 120 and the drain bus line114 are covered with a protecting film 131, and the pixel electrode 116is disposed on the protecting film 131. The pixel electrode 116 is madeof a transparent conductive film of ITO (Indium-Tin Oxide) or the like,and is electrically connected to the source electrode 122 of the TFT 120and the storage capacitor electrode 119 through contact holes 125 and126 formed in the protecting film 131. Besides, the two slits 145extending in oblique directions are formed in the pixel electrode 116 tobe almost linear symmetrical with respect to the storage capacitor busline. The surface of the pixel electrode 116 is covered with avertically aligned film (not shown) made of, for example, polyimide.

A light-shielding film (BM), a CF resin layer and a common electrode 141are formed on the opposite substrate disposed to be opposite to the TFTsubstrate 102. The plural bank-shaped linear projections 142 bent abovethe gate bus line 112 and the storage capacitor bus line 118 are formedon the common electrode 141. The linear projections 142 are arranged tobe shifted from the slits 145 of the pixel electrode 116 by a half pitchand in parallel therewith.

In the. MVA type liquid crystal display device as stated above, when aspecified voltage is applied between the pixel electrode 116 and thecommon electrode 141, as shown in FIG. 18 and. FIG. 20, four alignmentareas α, β, γ and δ are formed in which alignment directions of liquidcrystal molecules 108 are different from each other. The alignment areasα to δ are divided while the linear projection 142 and the slit 145 aremade boundaries. When the linear projection 142 and the slit 145 areformed so that the areas of the alignment areas α to δ become almostequal to each other in one pixel, the direction dependency of theviewing angle characteristic of the liquid crystal display devicebecomes low.

In the conventional MVA type liquid crystal display device, there occursa phenomenon in which when a screen is viewed from an oblique direction,it becomes whitish. FIG. 21 is a graph showing transmissivitycharacteristics (T-V characteristics) with respect to applied voltage inthe conventional MVA type liquid crystal display device. The horizontalaxis indicates the applied voltage (V) to the liquid crystal layer, andthe vertical axis indicates the light transmissivity. A curved line Lindicates a T-V characteristic in a direction (hereinafter referred toas a front direction) perpendicular to a display screen, and a curvedline M indicates a T-V characteristic in a direction (hereinafterreferred to as an oblique direction) in which an azimuth angle is 90°with respect to the display screen and a polar angle is 60°. Here, theazimuth angle is an angle measured in a counterclockwise direction withrespect to the right direction of the display screen. The polar angle isan angle formed relative to a perpendicular line standing at the centerof the display screen.

As shown in FIG. 21, when a relatively high voltage of about 3 V orhigher is applied to the liquid crystal layer, the transmissivity in thefront direction is higher than the transmissivity in the obliquedirection. On the other hand, when a voltage of about 2 to 3 V slightlyhigher than a threshold voltage is applied (region surrounded by acircle), the transmissivity in the oblique direction becomes higher thanthe transmissivity in the front direction. As a result, in the casewhere the display screen is viewed from an oblique direction, abrightness difference in an effective drive voltage range becomes small.This phenomenon appears most remarkably in the change of color. That is,since the brightness difference of the three primary colors of R, G andB becomes small, when viewed from the oblique direction, there occurs aphenomenon in which the color of the whole screen becomes whitish, andthe reproducibility of the colors is lowered. This phenomenon is calleddiscolor. The discolor occurs not only in the MVA type liquid crystaldisplay device but also in the TN mode liquid crystal display device.

Patent document 1 (U.S. Pat. No. 4,840,460) proposes that one pixel isdivided into plural sub-pixels, and those sub-pixels are capacitycoupled. In such a liquid crystal display device, since a potential isdivided based on the capacitance ratio of the respective sub-pixels,voltages different from each other can be applied to the liquid crystalsof the respective sub-pixels. Accordingly, apparently, plural regionsdifferent in the threshold of the T-V characteristic exist in one pixel.As stated above, when the plural regions different in the threshold ofthe T-V characteristic exist in one pixel, the phenomenon in which thetransmissivity in the oblique direction becomes higher than thetransmissivity in the front direction, as shown in the circle of FIG.21, is suppressed, and as a result, the phenomenon in which the screenbecomes whitish is also suppressed. As stated above, a method in whichone pixel is divided into plural capacity-coupled sub-pixels to improvethe display characteristic is called a capacitive coupling HT (half tonegray scale) method.

Patent document 2 (JP-A-5-66412) discloses a liquid crystal displaydevice having a structure in which as shown in FIG. 22, a pixelelectrode is divided into four sub-pixel electrodes 116 a to 116 d, andcontrol capacitance electrodes 117 a to 117 d are disposed below therespective sub-pixel electrodes 116 a to 116 d through an insulatingfilm. In this liquid crystal display device, the sizes of the controlcapacitance electrodes 117 a to 117 d are different from each other, anddisplay voltage is applied to the control capacitance electrodes 117 ato 117 d through a TFT 120. Besides, in order to prevent light fromleaking between the sub-pixel electrodes 116 a to 116 d, a controlcapacitance electrode 115 is disposed also between the sub-pixelelectrodes 116 a to 116 d.

Patent document 3 (JP-A-6-332009) also discloses a liquid crystaldisplay device in which one pixel is divided into plural sub-pixels. Inthis liquid crystal display device, for example, a rubbing processingcondition is changed for each sub-pixel, and pre-tilt angles of liquidcrystal molecules of the sub-pixels are made different from each other.

All of these conventional techniques relate to the TN mode liquidcrystal display device.

FIG. 23 shows a structure of one pixel of a conventional MVA type liquidcrystal display device using the capacitive coupling HT method. FIG. 24shows a sectional structure of the liquid crystal display device cutalong line Y-Y of FIG. 23. As shown in FIG. 23 and FIG. 24, a TFTsubstrate 102 includes plural gate bus lines 112 formed on a glasssubstrate 110, and plural drain bus lines 114 crossing the gate buslines 112 through an insulating film 130. The pitch of the gate buslines 112 is, for example, about 300 μm, and the pitch of the drain buslines 114 is, for example, about 100 μm. Rectangular pixel areas aredefined by the gate bus lines 112 and the drain bus lines 114. Besides,on the TFT substrate 102, a storage capacitor bus line 118 is formed tobe arranged in parallel with the gate bus line 112 and to cross thecenter of each of the pixel areas.

A TFT 120, control capacitance electrodes 133 and 134, and pixelelectrodes 116 a to 116 d are formed for each of the pixel areas on theTFT substrate 102. The pixel electrodes 116 a to 116 d are mutuallydivided by slits 145. The slits 145 are extended in oblique directions,and are formed to be almost linear symmetrical with respect to thestorage capacitor bus line 118.

The TFT 120 uses a part of the gate bus line 112 as its gate electrode.A drain electrode 121 of the TFT 120 is electrically connected to thedrain bus line 114. A source electrode 122 is disposed at a positionopposite to the drain electrode 121 through a channel protecting film128 formed on the gate bus line 112. Besides, the source electrode 122is electrically connected to the control capacitance electrodes 133 and134.

The sub-pixel electrodes 116 a to 116 d are made of transparentelectrode films of ITO or the like, and are mutually formed in the samelayer. The width of the slit 145 to separate these sub-pixel electrodes116 a to 116 d is, for example, 10 μm. The sub-pixel electrode 116 a iselectrically connected to the control capacitance electrode 133 througha contact hole 125, and the sub-pixel electrode 116 d is electricallyconnected to the control capacitance electrode 133 through a contacthole 127. Partial areas of the sub-pixel electrodes 116 b and 116 coverlap with the control capacitance electrode 133 (134) through aprotecting film 131. The sub-pixel electrodes 116 b and 116 c areindirectly connected to the control capacitance electrodes 133 and 134by capacitive coupling through the control capacitance formed in thearea. The control capacitance electrode 134 opposite to the storagecapacitor bus line 118 through the insulating film 130 functions also asone electrode of the storage capacitor formed for each pixel while thestorage capacitor bus line 118 is made the other electrode. Thesub-pixel electrodes 116 a to 116 d are covered with a verticallyaligned film 150 made of, for example, polyimide.

On the other hand, BMs 148 are formed on an opposite substrate 104. TheBMs 148 are made of metal material such as, for example, Cr (chromium),and are disposed at positions opposite to the gate bus line 112 on theTFT substrate 102 side, the storage capacitor bus line 118, the drainbus line 114, and the TFT 120. A CF resin layer 140 is formed on the BM148. The CF resin layer 140 of one color of R, G and B is disposed ineach of the pixels.

A common electrode 141 made of a transparent conductive film of ITO orthe like is formed on the CF resin layer 140. A bank-shaped linearprojection 142 as an alignment regulating structure is formed on thecommon electrode 141. As shown in FIG. 23, the linear projection 142 isbent above the gate bus line 112 and the storage capacitor bus line 118,and is formed to be shifted from the slit 145 of the TFT substrate 102by a half pitch and to be arranged in parallel therewith. The surfacesof the common electrode 141 and the linear projection 142 are coveredwith a vertically aligned film 151 made of, for example, polyimide.

When a specified gradation voltage is applied to the drain bus line 114,and a scanning signal is supplied to the gate bus line 112, the TFT 120is turned on. When the TFT 120 is turned on, the gradation voltage isapplied to the sub-pixel electrodes 116 a and 116 d electricallyconnected to the source electrode 122 and the control capacitanceelectrodes 133 and 134. Besides, since the sub-pixel electrodes 116 band 116 c are capacity coupled to the control capacitance electrode 133(134), the specified voltage is applied also to the sub-pixel electrodes116 b and 116 c.

However, in the structure shown in FIG. 23 and FIG. 24, since the areaof the sub-pixel electrode 116 c is smaller than that of the sub-pixelelectrode 116 b, and an overlapping area with the control capacitanceelectrode 133 (134) is large, the voltage of the sub-pixel electrode 116c becomes higher than the voltage of the sub-pixel electrode 116 b. Whenthe voltage of the sub-pixel electrode 116 a is A, the voltage of thesub-pixel electrode 116 b is B, the voltage of the sub-pixel electrode116 c is C, and the voltage of the sub-pixel electrode 116 d is D,A=D>C>B is established.

When the voltages are applied to the sub-pixel electrodes 116 a to 116 das stated above, the liquid crystal molecules are inclined in thedirection perpendicular to the direction in which the linear projection142 and the slit 145 extend. At this time, the inclined directions ofthe liquid crystal molecules become opposite directions at both sides ofeach of the linear projection 142 and the slit 145. Since the differentvoltages are applied to the sub-pixel electrodes 116 a and 116 d, thesub-pixel electrode 116 b and the sub-pixel electrode 116 c, apparently,three areas where the thresholds of the T-V characteristics are mutuallydifferent exist in one pixel. By this, the phenomenon is suppressed inwhich when the screen is viewed from the oblique direction, the screenbecomes whitish.

However, in the liquid crystal display device shown in FIG. 23 and FIG.24, since the control capacitance electrodes 133 and 134 are formed ofmetal layers which are the same layers as the source electrode 122 andthe drain electrode 121 and shield the light, there is a problem thatthe aperture ratio of the pixel is lowered and the brightness islowered.

Besides, according to the film thickness of the protecting film 131formed between the pixel electrodes 116 b, 116 c and the controlcapacitance electrodes 133, 134, light transmissivity, color viewingangle, the shift amount of a common potential and the like are degraded,and there is a problem that an excellent display quality can not beobtained.

SUMMARY OF THE INVENTION

The present invention has an object to provide a liquid crystal displaydevice having high brightness and excellent display quality.

The object is achieved by a liquid crystal display device including apair of substrates disposed to be opposite to each other, a liquidcrystal sealed between the pair of substrates, a plurality of pixelareas each including a first pixel electrode formed on one of thesubstrates and a second pixel electrode formed on the one substrate andseparated from the first pixel electrode, a transistor disposed in eachof the pixel areas and including a source electrode electricallyconnected to the first pixel electrode, a linear alignment regulatingstructure formed on the other substrate and to regulate alignment of theliquid crystal, and a control capacitance section to capacity couple thesource electrode and the second pixel electrode and including a controlcapacitance electrode which is electrically connected to the sourceelectrode, is opposite to at least part of the second pixel electrodethrough an insulating film, and at least part of which is disposed tooverlap with the alignment regulating structure when viewedperpendicularly to a substrate surface and extends along the alignmentregulating structure.

According to the invention, the liquid crystal display device havinghigh brightness and excellent display quality can be realized.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a view showing a rough structure of a liquid crystal displaydevice according to a first embodiment of the invention;

FIG. 2 is a view showing a structure of one pixel of the liquid crystaldisplay device according to the first embodiment of the invention;

FIG. 3 is a sectional view showing a structure of the liquid crystaldisplay device according to the first embodiment of the invention;

FIG. 4 is a view schematically showing a pixel area P, a linearprojection 42, and a connection part 33 b of a control capacitanceelectrode 33;

FIG. 5 is a graph showing a relation between film thickness of aprotecting film 31 and light transmissivity of a pixel;

FIG. 6 is a graph showing a relation between the film thickness of theprotecting film 31 and color viewing angle;

FIG. 7 is a graph showing a relation between the film thickness of theprotecting film 31 and the shift amount ΔVcom of a common potential;

FIG. 8 is a view showing a structure of a B pixel of a liquid crystaldisplay device according to a second embodiment of the invention;

FIG. 9 is a view showing a structure of an R pixel or a G pixel of theliquid crystal display device according to the second embodiment of theinvention;

FIGS. 10A and 10B are views showing sectional structures of the liquidcrystal display device according to the second embodiment of theinvention;

FIGS. 11A and 11B are sectional views showing structures of an oppositesubstrate 4 before being bonded to a TFT substrate 2;

FIGS. 12A and 12B are sectional views showing structures of the TFTsubstrate 2 before being bonded to the opposite substrate 4;

FIGS. 13A to 13E are views showing manufacturing steps of the oppositesubstrate 4;

FIGS. 14A to 14F are views showing manufacturing steps of a liquidcrystal display panel using an ODP method;

FIG. 15 is a view showing a rough sectional structure of a conventionalliquid crystal display device;

FIGS. 16A and 16B are views schematically showing sectional structuresof an MVA type liquid crystal display device;

FIG. 17 is a view schematically showing another example of a sectionalstructure of an MVA type liquid crystal display device;

FIG. 18 is a view showing a structure of one pixel of an MVA type liquidcrystal display device;

FIG. 19 is a view showing a sectional structure of the MVA type liquidcrystal display device;

FIG. 20 is a view schematically showing alignment directions of liquidcrystal molecules of the MVA type liquid crystal display device;

FIG. 21 is a graph showing T-V characteristics of the MVA type liquidcrystal display device;

FIG. 22 is a view showing a structure of a liquid crystal display devicedisclosed in patent document 2;

FIG. 23 is a view showing a structure of one pixel of a conventional MVAtype liquid crystal display device using a capacitive coupling HTmethod; and

FIG. 24 is a view showing a sectional structure of the conventional MVAtype liquid crystal display device using the capacitive coupling HTmethod.

DETAILED DESCRIPTION OF THE INVENTION First Embodiment

A liquid crystal display device according to a first embodiment of theinvention will be described with reference to FIGS. 1 to 7. FIG. 1 showsa rough structure of the liquid crystal display device according to thisembodiment. As shown in FIG. 1, the liquid crystal display deviceincludes a TFT substrate 2 on which gate bus lines and drain bus linesare formed to cross each other through an insulating film, and on whicha TFT and a pixel electrode are formed for each pixel. Besides, theliquid crystal display device includes an opposite substrate 4 on whicha CF and a common electrode are formed and which is disposed to beopposite to the TFT substrate 2, and a vertically aligned liquid crystal6 (not shown in FIG. 1) sealed between both the substrates 2 and 4 andhaving negative dielectric anisotropy.

The TFT substrate 2 is connected with a gate bus line drive circuit 80in which a driver IC to drive the plural gate bus lines is mounted and adrain bus line drive circuit 82 in which a driver IC to drive the pluraldrain bus lines is mounted. These drive circuits 80 and 82 output ascanning signal and a data signal to a specified gate bus line or drainbus line based on a specified signal outputted from a control circuit84. A polarizing plate 87 is disposed on a surface of the TFT substrate2 opposite to a TFT element formation surface thereof, and a polarizingplate 86 disposed in crossed Nicols with respect to the polarizing plate87 is disposed on a surface of the substrate 4 opposite to a commonelectrode formation surface thereof. A backlight unit 88 is disposed tobe opposite to the TFT substrate 2 across the polarizing plate 87 and isdisposed on a surface thereof.

FIG. 2 shows a structure of one pixel of an MVA type liquid crystaldisplay device, as the liquid crystal display device of this embodiment,using a capacitive coupling HT method when viewed from the oppositesubstrate 4 side. FIG. 3 shows a sectional structure of the liquidcrystal display device cut along line C-C of FIG. 2. As shown in FIG. 2and FIG. 3, the TFT substrate 2 of the liquid crystal display device ofthis embodiment includes plural gate bus lines 12 formed on atransparent thin plate such as a glass substrate 10, and plural drainbus lines 14 crossing the gate bus lines 12 through an insulating film30. The pitch of the gate bus lines 12 is, for example, about 300 μm,and the pitch of the drain bus lines 14 is, for example, about 100 μm.Besides, on the TFT substrate 2, storage capacitor bus lines 18 arrangedin parallel to the gate bus lines 12 are formed in the same layer as thegate bus lines 12.

For example, a channel etch type TFT 20 is formed in the vicinity of across position of the gate bus line 12 and the drain bus line 14. A gateelectrode 23 of the TFT 20 is electrically connected to the gate busline 12. An operating semiconductor layer 28 is formed on the gateelectrode 23. A rod-like source electrode 22 and a C-shaped drainelectrode 21 surrounding the source electrode 22 through a specified gapare formed on the operating semiconductor layer 28. The drain electrode21 is electrically connected to the drain bus line 14.

A protecting film 31 made of, for example, a silicon nitride film (SiNfilm) is formed on the whole substrate surface on the TFT 20. Pixelelectrodes 16 a and 16 b are formed on the protecting film 31 and ineach intersection part of the gate bus lines 12 and the drain bus lines14. A rectangular area in which the pixel electrodes 16 a and 16 b areformed is a pixel area. The pixel area is divided into a sub-pixel A inwhich the pixel electrode 16 a is formed and a sub-pixel B in which thepixel electrode 16 b is formed. The sub-pixel A has, for example, atrapezoidal shape, and is disposed at the center left of the pixel area.The sub-pixel B is disposed at the upper part, the lower part and thecenter right end of the pixel area in FIG. 2 except the sub-pixel A. Thearrangement of the sub-pixels A and B is almost line symmetrical in onepixel with respect to the storage capacitor bus line 18. The pixelelectrodes 16 a and 16 b are made of transparent conductive films of,for example, ITO or the like, and are respectively formed in the samelayer.

The pixel electrodes 16 a and 16 b are separated from each other byslits 44, 47 and 44 surrounding three sides of the trapezoidal pixelelectrode 16 a to form a substantially C shape. The slit 44 extendsobliquely to the end of the pixel area, and the slit 47 extends alongthe right end of the pixel area. The width of the slits 44, 47 is, forexample 10 μm. The slit 44 functions also as an alignment regulatingstructure to regulate the alignment of the liquid crystal.

A control capacitance electrode 33 is formed in the sub-pixel B. Thecontrol capacitance electrode 33 is electrically connected to the sourceelectrode 22, and is formed in the same layer as, for example, thesource electrode 22. The control capacitance electrode 33 includesoblique extension parts 33 a and 33 c arranged in parallel to the slits44 and extending obliquely to the end of the pixel area, and aconnection part 33 b extending along the right long side of the pixelarea in FIG. 2 and connecting the oblique extension parts 33 a and 33 c.The control capacitance electrode 33 is disposed to overlap with apartial area of the pixel electrode 16 b through the protecting film(insulating film) 31. A control capacitance Cc is formed as a controlcapacitance section between the pixel electrode 16 b and the capacitanceelectrode 33 in the area where they are opposite to each other throughthe protecting film 31.

A storage capacitor electrode 19 is formed on the storage capacitor busline 18 through the insulating film 30 for each pixel. A storagecapacitor Cs is formed between the storage capacitor bus line 18 and thestorage capacitor electrode 19 opposite to each other through theinsulating film 30. The storage capacitor electrode 19 is electricallyconnected to the pixel electrode 16 a through a contact hole 25 openedin the protecting film 31. Besides, the storage capacitor electrode 19is electrically connected to the control capacitance electrode 33 andthe source electrode 22.

The pixel electrode 16 a of the sub-pixel A is electrically connected tothe source electrode 22 of the TFT 20 through the storage capacitorelectrode 19 and the control capacitance electrode 33. On the otherhand, the pixel electrode 16 b of the sub-pixel B is electrically in afloating state. The pixel electrode 16 b is indirectly connected to thesource electrode 22 by capacitive coupling through the controlcapacitance Cc. The pixel electrodes 16 a and 16 b and the protectingfilm 31 are covered with a vertically aligned film 50 made of, forexample, polyimide.

On the other hand, the opposite substrate 4 includes a BM 48 which isformed on a glass substrate 11 and shields the end of the pixel area.The BM 48 is formed of metal material such as, for example, Cr, and isdisposed at positions opposite to the gate bus line 12 on the TFTsubstrate 2 side, the drain bus line 14 and the TFT 20. An opening 48 aof the BM 48 is narrower than the pixel area in which the pixelelectrodes 16 a 16 b are formed in view of a bonding shift of both thesubstrates 2 and 4. A CF resin layer 40 is formed on the BM 48. The CFresin layer 40 of one color of R, G and B is disposed in each pixel.

A common electrode 41 made of a transparent conductive film of ITO orthe like is formed on the CF resin layer 40. A liquid crystalcapacitance Clc1 is formed between the pixel electrode 16 a of thesub-pixel A and the common electrode 41 opposite to each other throughthe liquid crystal layer, and a liquid crystal capacitance Clc2 isformed between the pixel electrode 16 b of the sub-pixel B and thecommon electrode 41. A bank-shaped linear projection 42 as an alignmentregulating structure is formed on the common electrode 41. The linearprojection 42 is formed by using a photosensitive resin or the like. Thelinear projection 42 is bent above the gate bus line 12 and the storagecapacitor bus line 18, and is disposed in parallel to the slit 44 of theTFT substrate 2. The width of the linear projection 42 is about 8 to 12μm (for example, 10 μm), and the height is about 1 to 1.6 μm. Thesurfaces of the common electrode 41 and the linear projection 42 arecovered with a vertically aligned film 51 made of, for example,polyimide. Incidentally, as the alignment regulating structure on theopposite substrate 4, a slit obtained by partially removing the commonelectrode 41 may be formed instead of the linear projection 42.

It is assumed that the TFT 20 is turned on, a specified voltage isapplied to the pixel electrode 16 a, and a voltage Vpx1 is applied tothe liquid crystal layer of the sub-pixel A. At this time, since thepotential is divided in accordance with the capacitance ratio of theliquid crystal capacitance Clc2 and the control capacitance Cc, avoltage different from that of the pixel electrode 16 a is applied tothe pixel electrode 16 b of the sub-pixel B. A voltage Vpx2 applied tothe liquid crystal layer of the sub-pixel B isVpx2=(Cc/(Clc2+Cc))×Vpx1.Where, because of 0<(Cc/(Clc2+Cc))<1, except Vpx1=Vpx2=0, the voltageVpx2 becomes smaller than the voltage Vpx1 (|Vpx2|<|Vpx1|). As statedabove, in the liquid crystal display device of this embodiment, thevoltage Vpx1 applied to the liquid crystal layer of the sub-pixel A andthe voltage Vpx2 applied to the liquid crystal layer of the sub-pixel Bcan be made different from each other in one pixel. By this, since thedistortion of the T-V characteristic is dispersed in one pixel, thephenomenon is suppressed in which the color of an image becomes whitishwhen viewed from an oblique direction, and the liquid crystal displaydevice can be obtained in which the viewing angle characteristic isimproved and the viewing angle is wide.

Here, at least part of the oblique extension parts 33 a and 33 c of thecontrol capacitance electrode 33 formed on the TFT substrate 2 extendsalong the linear projections 42 formed on the opposite substrate 4, andis disposed to overlap with the linear projections 42 when viewedperpendicularly to the substrate surface. The widths of the obliqueextension parts 33 a and 33 c (and the connection part 33 b) arenarrower than the width of the linear projection 42. In this example,each of the oblique extension parts 33 a and 33 c is disposed inside ofboth side ends of the linear projection 42 when viewed perpendicularlyto the substrate surface, and substantially the whole region of theoblique extension parts 33 a, 33 c overlaps with the linear projection42. Besides, at least part of the control capacitance electrode 33 isdisposed to overlap with the BM 48 when viewed perpendicularly to thesubstrate surface. For example, an area having an area ratio of 60% ormore in the connection part 33 b overlaps with the BM 48.

In the formation area of the linear projection 42 in the pixel, thelight transmissivity is low as compared with the other area. In thisembodiment, at least part of the control capacitance electrode 33 isdisposed to overlap with the linear projection 42, so that thesubstantial aperture ratio of the pixel is improved, and as comparedwith the related art, a further bright display is enabled. Similarly, atleast part of the control capacitance electrode 33 is disposed tooverlap with the BM 48 to shield the light, so that the aperture ratioof the pixel is improved, and as compared with the related art, afurther bright display is enabled.

The voltage ratio Vpx2/Vpx1 (=Cc/(Clc2+Cc)) of the sub-pixels A and Bbecomes large (approaches 1) as the capacitance ratio Cc/Clc2 becomeslarge, and it becomes small (approaches 0) as the capacitance ratioCc/Clc2 becomes small. Accordingly, the voltage ratio Vpx2/Vpx1 can bechanged by adjusting the control capacitance Cc. The control capacitanceCc is determined by the overlap area between the control capacitanceelectrode 33 and the pixel electrode 16 b, the film thickness of theprotecting film 31, and the dielectric constant of the formationmaterial of the protecting film 31. However, in this embodiment, sinceSiN is used as the formation material of the protecting film 31, thedielectric constant is almost constant.

FIG. 4 schematically shows a structure, when viewed from the TFTsubstrate 2 side, of the pixel area P in which the pixel electrodes 16 aand 16 b (and the slits 44 and 47) are formed, the linear projection 42,and the connection part 33 b of the control capacitance electrode 33. Asshown in FIG. 4, the pixel area P has a rectangular shape with a shortside of a length X and a long side of a length 3X. The length X is about50 to 100 μm, for example, 65 μm. The linear projection 42 in the pixelarea P has two regions which pass two corner parts located at both endsof the right long side of the pixel area P in the drawing and linearlyextend in directions each of which forms an angle of 45° with respect tothe long side and which are almost perpendicular to each other. Thewidth of the linear projection 42 is Y (for example, 10 μm). The overlapwidths between the oblique extension parts 33 a and 33 c (not shown inFIG. 4) of the control capacitance electrode 33 respectively extendingalong the two regions and the linear projections 42 are, for example, 7μm. The connection part 33 b of the control capacitance electrode 33extends along the left long side of the pixel area P in the drawing. Thelength of the connection part 33 b is X equal to the length of the shortside of the pixel area P, and the width of the connection part 33 b is Z(about 2 to 15 μm (for example, 5 μm)). In this embodiment, the area Sof the control capacitance electrode 33 in the pixel area P (that is,the overlap area between the control capacitance electrode 33 and thepixel electrode 16 b) satisfies a relation of expression (1).S≦(Y×√(X ² +X ²)−Y ²/2)×2+X×Z  (1)

For example, in the case of X=65 (μm), Y=10 (μm) and Z=5 (μm), the areaS is made almost 2100 μm² or less. In this example, the area S is made1146.07 μm². Incidentally, in the case where the size of the pixel areaP is different, the widths of the oblique extension parts 33 a and 33 cof the control capacitance electrode 33 are changed, or the length ofthe oblique extension part 33 c is changed to adjust the area S of thecontrol capacitance electrode 33.

FIG. 5 is a graph showing a relation between the film thickness of theprotecting film 31 in the case of the area S of 1146.07 μm² and thelight transmissivity of the pixel at the time when a specified voltageis applied. The horizontal axis indicates the film thickness (nm), andthe vertical axis indicates the transmissivity. As shown in FIG. 5, asthe film thickness of the protecting film 31 becomes large, the lighttransmissivity is decreased. When the film thickness of the protectingfilm 31 is made almost 300 nm or less, even when consideration is givento the variation of the area S within the range of satisfying theexpression (1), the light transmissivity of 3.0% or more is obtained,and it is understood that the liquid crystal display device with highbrightness can be realized.

FIG. 6 is a graph showing a relation between the film thickness of theprotecting film 31 in the case of the area S of 1146.07 μm² and thecolor viewing angle (Δu′v′<0.04). The horizontal axis indicates the filmthickness (nm), and the vertical axis indicates the color viewing angle(deg). As shown in FIG. 6, as the film thickness of the protecting film31 becomes small, the color viewing angle is decreased. When the filmthickness of the protecting film 31 is made about 100 nm or more, evenwhen consideration is given to the variation of the area S within therange of satisfying the expression (1), the color viewing angle of 130°or more is obtained, and it is understood that the liquid crystaldisplay device in which the discolor does not occur can be realized.From the graphs shown in FIG. 5 and FIG. 6, it is understood that whenthe film thickness of the protecting film 31 is made not less than about100 nm and not larger than 300 nm (for example, 200 nm), the liquidcrystal display device can be obtained in which the brightness is high,the discolor does not occur, and the display quality is excellent.Incidentally, in this example, the control capacitance Cc is about 305to 405 fF (for example, 355.2 fF). Besides, in the case where the filmthickness of the protecting film 31 is made 200 nm, the range of thearea S in which excellent display quality is obtained is approximatelyfrom 980 to 1325 μm².

FIG. 7 is a graph showing a relation between the film thickness of theprotecting film 31 in the case where the area S is 1146.07 μm² and theshift amount ΔVcom of a common potential. The horizontal axis indicatesthe film thickness (nm), and the vertical axis indicates the shiftamount ΔVcom (V) of the common potential at 223 gradations in the casewhere white is displayed for 120 minutes. As shown in FIG. 7, as thefilm thickness of the protecting film 31 becomes large, the shift amountΔVcom becomes large. As stated above, when the film thickness of theprotecting film 31 is made 300 nm (100 nm or more), the shift amountΔVcom of the common potential is suppressed to about 0.47 V or less, andit is understood that burn-in or the like hardly occurs, and excellentdisplay quality is obtained.

Next, a manufacturing method of the liquid crystal display deviceaccording to this embodiment will be described with reference to FIG. 2and FIG. 3. First, the manufacturing method of the TFT substrate 2 willbe described.

A metal film made of Cr or a metal film having a laminate structure ofAl (aluminum) and Ti (titanium) is formed by, for example, a PVD(Physical Vapor Deposition) method on the glass substrate 10.Thereafter, a photolithography method is used to pattern this metal filmto form the gate bus line 12, the gate electrode 23 and the storagecapacitor bus line 18. Incidentally, in order to prevent impurities fromdiffusing from the glass substrate 10, the metal film may be formedafter the surface of the glass substrate 10 is covered with aninsulating film.

Next, silicon oxide or silicon nitride is deposited on the gate bus line12, the gate electrode 23 and the storage capacitor bus line 18 and onthe whole substrate surface by, for example, a CVD (Chemical VaporDeposition) method, and the insulating film 30 covering the gate busline 12 and the storage capacitor bus line 18 is formed.

Next, an amorphous silicon (a-Si) film (or polysilicon (p-Si) film)having a thickness of 80 to 200 nm and an a-Si film (n⁺a-Si film) inwhich an n-type impurity is introduced at high concentration aresuccessively formed on the whole surface of the insulating film 30 byusing, for example, the CVD method. Thereafter, the n⁺a-Si film and thea-Si film (or p-Si film) are patterned by the photolithography method toform island regions, and an ohmic contact layer 29 of the TFT 20 and theoperating semiconductor layer 28 are formed.

Next, a metal film having a laminate structure of, for example, Ti—Al—Tiis formed on the ohmic contact layer 29 and on the whole substratesurface. The metal film, the ohmic contact layer 29 and the operatingsemiconductor layer 28 are patterned by the photolithography method todefine the shape of the operating semiconductor layer 28 of the TFT 20and to form the drain bus line 14, the source electrode 22, the drainelectrode 21, the control capacitance electrode 33 and the storagecapacitor electrode.

Next, silicon nitride of 200 nm is deposited on the drain bus line 14and the like and the whole substrate surface by, for example, the CVDmethod to form the protecting film 31. Then, the contact hole 25 leadingto the storage capacitor electrode 19 is formed at a specified positionof the protecting film 31 by the photolithography method.

Next, an ITO film is formed on the protecting film 31 and on the wholesurface by the sputtering method. Thereafter, the ITO film is patternedby the photolithography method to form the pixel electrodes 16 a and 16b. The pixel electrode 16 a is electrically connected to the storagecapacitor electrode 19 through the contact hole 25. Next, polyimide iscoated on the pixel electrodes 16 a and 16 b and on the whole substratesurface to form the vertically aligned film 50. The TFT substrate 2 iscompleted in this way.

Next, a manufacturing method of the opposite substrate 4 will bedescribed. First, a metal film of, for example, Cr is formed on thewhole surface of the glass substrate 11. This metal film is patterned toform the BM 48 at positions corresponding to the gate bus line 12 on theTFT substrate 2 side, the drain bus line 14 and the TFT 20.

Next, for example, a red photosensitive resin, a green photosensitiveresin, and a blue photosensitive resin are used to successively form theCF resin layers 40 of R, G and B in each pixel area. The CF resin layer40 of one color of red, green and blue is disposed for each pixel.

Next, an ITO film is formed on the CF resin layer 40 by the sputteringmethod, and the common electrode 41 is formed. Next, for example, aphotoresist is used to form the bank-shaped linear projection 42 made ofa dielectric on the common electrode 41. Next, polyimide is coated onthe common electrode 41 and the linear projection 42 and on the wholesubstrate surface to form the vertically aligned film 50. The oppositesubstrate 4 is completed in this way.

The TFT substrate 2 and the opposite substrate 4 fabricated through theabove process are boned to each other through, for example, a sphericalspacer. Next, the vertically aligned liquid crystal 6 having negativedielectric anisotropy is injected and sealed between the TFT substrate 2and the opposite substrate 4. In this way, the liquid crystal displaydevice of this embodiment is completed. As described above, according tothis embodiment, the liquid crystal display device having highbrightness and excellent display quality can be obtained.

Second Embodiment

Next, a liquid crystal display device according to a second embodimentof the invention will be described with reference to FIGS. 8 to 14F.FIG. 8 shows a structure of a B pixel (pixel in which a blue CF resinlayer is formed) of the liquid crystal display device of thisembodiment, and FIG. 9 shows a structure of an R pixel or a G pixel(pixel in which a red or a green CF resin layer is respectively formed)of the liquid crystal display device of this embodiment. FIG. 10A showsa sectional structure of the liquid crystal display device cut alongline D-D of FIG. 8, and FIG. 10B shows a sectional structure of theliquid crystal display device cut along line E-E of FIG. 9. FIG. 11A andFIG. 11B show sectional structures of an opposite substrate 4 beforebeing bonded to the TFT substrate 2. FIG. 11A shows the sectionalstructure of the opposite substrate 4 cut at the same position as FIG.10A, and FIG. 11B shows the sectional structure of the oppositesubstrate 4 cut at the same position as FIG. 10B. FIG. 12A and FIG. 12Bshow sectional structures of the TFT substrate 2 before being bonded tothe opposite substrate 4. FIG. 12A shows the sectional structure of theTFT substrate 2 cut at the same position as FIG. 10A, and FIG. 12B showsthe sectional structure of the TFT substrate 2 cut at the same positionas FIG. 10B.

As shown in FIGS. 8 to 12B, in this embodiment, the B pixel is differentfrom the R pixel or the G pixel in the structure on the TFT substrate 2side. The B pixel of the TFT substrate 2 has almost the same structureas that of FIG. 2. In the B pixel on the opposite substrate 4 side, acolumn spacer 45 made of, for example, acrylic resin negativephotosensitive resist is formed in a region where a connection part 33 band a storage capacitor electrode 19 cross each other to form a T shape.When the structures of the formation region of the column spacer 45 anda pixel opening part on the TFT substrate 2 side are compared with eachother, the formation region of the column spacer 45 includes a storagecapacitor bus line 18 formed in the same layer as a gate electrode 23 ofa TFT 20, an a-Si layer 62 formed in the same layer as an operatingsemiconductor layer 28, an n⁺a-Si layer 61 formed in the same layer asan ohmic contact layer 29, and the connection part 33 b (storagecapacitor electrode 19) formed in the same layer as a source electrode22 and a drain electrode 21. By this, a protrusion 63 having a height T1is formed in the formation region of the column spacer 45. The columnspacer 45 and the protrusion 63 constitute a first cell gap keepingstructure. The first cell gap keeping structure is in contact with boththe opposite substrate 4 and the TFT substrate 2, and keeps a cell gapG1.

A column spacer 46 in the same layer as the column spacer 45 is formedon the opposite substrate 4 of the R pixel and the G pixel. Differentlyfrom the structure of the B pixel, a connection part 33 b and a storagecapacitor electrode 19 of the R pixel and the G pixel are disposed todetour around the formation region of the column spacer 46. Accordingly,although the formation region of the column spacer 46 has the storagecapacitor bus line 18, as compared with the formation region of thecolumn spacer 45, the a-Si layer 62, the n⁺a-Si layer 61 and theconnection part 33 b are not provided. By this, a protrusion 64 having aheight T2 lower than the protrusion 63 by the sum total of therespective film thicknesses of the a-Si layer 62, the n⁺a-Si layer 61and the connection part 33 b are formed in the formation region of thecolumn spacer 46 (T1>T2). In this example, the difference (T1−T2)between the height T1 and the height T2 is, for example, 0.50 μm. Thecolumn spacer 46 and the protrusion 64 constitute a second cell gapkeeping structure. A height C1 of the column spacer 45 from the commonelectrode 41 and a height C2 of the column spacer 46 from the commonelectrode 41 are almost equal to each other before the substrates arebonded (C1=C2), and are both, for example, 3.2 μm.

The liquid crystal display device according to this embodiment ismanufactured by using a one drop fill (ODF) method, and a sealingmaterial continuously coated to seal the liquid crystal is formed on theouter peripheral part between the substrates 2 and 4. The cell gap G1 ofthe liquid crystal display device manufactured using the ODF method isdetermined by the amount of liquid crystal to be dropped. In thisembodiment, the amount of liquid crystal to be dropped is determined sothat the cell gap G1 between the substrates 2 and 4 satisfies therelation of (T1+C1)<G1<(T2+C2). Accordingly, the column spacer 45 andthe protrusion 63 are contact with each other, and are compressed by(G1−(T2+C2)) (for example, 0.25 μm). On the other hand, the columnspacer 46 and the protrusion 64 are not in contact with each other andare opposite to each other through a gap of (G1−(T1+C1)) (for example,0.25 μm). That is, the first cell gap keeping structure including thecolumn spacer 45 and the protrusion 63 always keeps the cell gap G1, andthe second cell gap keeping structure including the column spacer 46 andthe protrusion 64 keeps the cell gap G2 (not shown) narrower than thecell gap G1 when pressure is applied from outside.

The upper bottom area (support area of the first cell gap keepingstructure) S1 of the column spacer 45 and the upper bottom area (supportarea of the second cell gap keeping structure) S2 of the column spacer46 are almost equal to each other (S1=S2), and are both, for example,300 μm². The column spacer 45 is disposed for every five B pixels, andthe column spacer 46 is disposed in every R pixel and every G pixel.Accordingly, the area density D1 of the first cell gap keeping structureis 1/10 of the area density D2 of the second cell gap keeping structure(D1:D2=1:10). Incidentally, the structure of the B pixel on the TFT 2side in which the column spacer 45 is not formed may be similar to thestructure of the R pixel and the G pixel on the TFT substrate 2 side.

For example, even in the case where the column spacer 45 is formed to belower by 0.15 μm because of manufacture variation, after the substratesare bonded to each other, the column spacer 45 (and the protrusion 63)is compressed by 0.10 μm. Accordingly, the manufactured liquid crystaldisplay panel has an inner pressure in which uneven gravity does notoccur. On the other hand, even in the case where the column spacer 46 isformed to be higher by 0.15 μm, after the substrates are bonded to eachother, since there is a gap of 0.10 μm between the column spacer 46 andthe protrusion 64, they are not in contact with each other at a roomtemperature. Accordingly, occurrence of bubbles at a low temperature canbe prevented.

Besides, when a high pressure is applied between the substrates 2 and 4of the liquid crystal display panel from outside, in addition to thefirst cell gap keeping structure, the second cell-gap keeping structurekeeps the cell gap. Accordingly, uneven cell gap does not occur, andhigh resistance to the outside pressure is obtained.

According to this embodiment, in addition to the same effect as thefirst embodiment, when pressure is not applied from outside, since onlythe first cell gap keeping structure formed at the low area density D1keeps the cell gap G1, the occurrence of bubbles at a low temperaturecan be prevented. On the other hand, when pressure is applied fromoutside, since the first and the second cell gap keeping structuresformed at a high area density (D1+D2) keep the cell gap G2, uneven cellgap can be suppressed. Besides, according to this embodiment, in theliquid crystal display device manufactured by using the ODF method, twocontradictory effects of a wide manufacture margin and high resistanceto pressure can be simultaneously realized.

Next, a manufacturing method of the liquid crystal display deviceaccording to this embodiment will be described in brief. FIGS. 13A to13E show manufacture steps of the opposite substrate 4. First, as shownin FIG. 13A, a BM 48 is formed on an insulating substrate, such as aglass substrate 11, by using Cr metal or resin black. Next, as shown inFIG. 13B, pigment dispersion photosensitive colored resin or the like isused to successively form CF resin layers 40R, 40G and 40B. Next, asshown in FIG. 13C, a transparent conductive film of ITO or the like issputtered to form a common electrode 41. Next, as shown in FIG. 13D, forexample, novolac resin positive type photosensitive resist is coated onthe whole substrate surface, and a linear projection 42 with a specifiedarrangement pattern is formed using a photolithography method. Next, asshown in FIG. 13E, for example, acrylic resin negative photosensitiveresist is coated on the whole substrate surface, and column spacers 45and 46 having specified upper bottom areas are formed at specifiedpositions by using the photolithography method. The column spacer 45 isdisposed at an arrangement density of, for example, one per five Bpixels, and the column spacer 46 is arranged in every R pixel and everyG pixel at an arrangement density of one per one. The opposite substrate4 is manufactured through the above steps.

FIGS. 14A to 14F are views showing manufacture steps of the liquidcrystal display panel using the ODF method. FIGS. 14A, 14C and 14E areperspective views showing states of the opposite substrate 4 atrespective steps, and FIGS. 14B, 14D and 14F are schematic sectionalviews showing states of the vicinity of the column spacer 45 (or 46) atthe respective steps. First, an alignment film is formed on the surfaceof the opposite substrate 4 and the TFT substrate 2 manufactured at aseparate step, and as shown in FIGS. 14A and 14B, a photo-curing sealingmaterial 60 is coated continuously on, for example, the whole outerperiphery of the opposite substrate 4. Next, as shown in FIGS. 14C and14D, a specified amount of liquid crystal 6 is dropped on the oppositesubstrate 4. Incidentally, FIG. 14D shows the liquid crystal 6 in astate where it is filled at an after-mentioned step, not the liquidcrystal 6 in a dropped state. Next, as shown in FIGS. 14E and 14F, theopposite substrate 4 and the TFT substrate 2 are bonded to each other invacuum, and pressure is returned to the atmospheric pressure so that theliquid crystal 6 is filled between the substrates 2 and 4. At this time,the cell gap is controlled by the drop amount of the liquid crystal 6,and the column spacer 45 comes in contact with the TFT substrate 2 andis compressed by a predetermined variation amount. After the sealingmaterial 60 is hardened, the liquid crystal display panel is completedthrough steps of panel cutting, polarizing plate bonding and the like.Thereafter, the liquid crystal display device is completed through amodule step and the like.

The invention is not limited to the above embodiments, but can bevariously modified.

For example, in the embodiments, although the transmission liquidcrystal display device is used as the example, the invention is notlimited to this, but can be applied to another liquid crystal displaydevice of a reflection type, semi-transmission type or the like.

Besides, in the embodiments, the liquid crystal display device includingthe pixel area having two sub-pixels is used as the example, theinvention is not limited to this, but can be applied to a liquid crystaldisplay device including a pixel area having three or more sub-pixels.

Further, in the embodiments, although the liquid crystal display deviceincluding the channel etch TFT is used as the example, the invention isnot limited to this, but can be applied to a liquid crystal displaydevice including a channel protection film type TFT.

1. A liquid crystal display device comprising: a first and secondsubstrate; an alignment regulating structure provided on the secondsubstrate; a plurality of pixel areas provided, each of the pixel areasincluding a first sub-pixel electrode and a second sub-pixel electrodeprovided on the first substrate; a transistor provided in each of thepixel areas, the transistor including gate, drain and source electrodes;a storage capacitor bus line provided on the first substrate andintersecting with at least one of the pixel areas; and a controlcapacitance electrode provided on the first substrate, the controlcapacitance electrode including a first portion which is electricallyconnected to the source electrode of the transistor, a second portionwhich is connected to the first sub-pixel electrode via a contact holeand which is entirely provided within an area where the first sub-pixelelectrode overlaps the storage capacitor bus line and a third portionbetween the first portion and the second portion, the third portionoverlapping the second sub-pixel electrode, wherein the source electrodeis closer to the first portion than the second portion.
 2. The liquidcrystal display device of claim 1, wherein an electrical path is formedon the first substrate between the source electrode and the firstsub-pixel electrode.
 3. The liquid crystal display device of claim 2,wherein the electrical path between the source electrode and the firstsub-pixel electrode is formed via the connection between the firstsub-pixel electrode and the second portion of the control capacitanceelectrode.
 4. The liquid crystal display device of claim 2, wherein thecontrol capacitance electrode includes an inclined portion at leastpartially overlapping the alignment regulating structure the inclinedportion of the control capacitance electrode is branched from theelectrical path.
 5. The liquid crystal display device of claim 1,wherein the control capacitance electrode is capacitively coupled withthe second sub-pixel electrode.
 6. The liquid crystal display device ofclaim 1, wherein the control capacitance electrode includes a portion atleast partially overlapping the alignment regulating structure.
 7. Theliquid crystal display device of claim 6, wherein the inclined portionof the control capacitance electrode and the storage capacitor bus lineforms an angle of 45 degrees.
 8. The liquid crystal display device ofclaim 1, wherein the alignment regulating structure is a linearprotrusion.
 9. The liquid crystal display device of claim 1, wherein thefirst portion is provided between the source electrode and a pointbefore an area where the control capacitance electrode overlaps thesecond sub-pixel electrode.
 10. The liquid crystal display device ofclaim 1, wherein the entire third portion overlaps the second sub-pixelelectrode.